In an earlier attempt at an integrated breakout board, two of the four I2C subsystems failed to work. The accelerometer was one of them, so I figured it would be a good acid test. If you go to SparkFun or Adafruit, you will so a whole plethera of breakoutboards, so it is a bit hard to choose. I decided on the LIS3DH because it was I2C, read up to 16g, and was fairly inexpensive. Another thing you will quickly recognize is that all of them are some form of BGA package, making hand assembly difficult (and ultimately why I failed earlier).
For hand soldering BGA, you pretty much have two choices: hot air or reflow. Either way, you life will be easier if you have a stencil. I get mine from OSH Stencil. I was already getting a stencil for another board, and just threw the footprint on. The other resistors and capacitors were hand soldered.
One of the advantages of using something SparkFun or Adafruit has done, is using their libraries. For the LIS3DH, there are actually two:
As for headers, as you will see with the battery problems, I'm still trying to figure it out. For now, I'm going with female on the main board (like Arduino) and male on the Bloks. I'm going to try and source some shorter headers.